Why can't they take a realistic tone with WW as well. If they can adapt all of this Kryptonian stuff into MOS and still have it be grounded and realistic, why can't Wonder Woman do the same?

Why can't they take the approach of 'What if this demi-god from a mythological land was actually here today?' if they can take that approach with an alien being with superhuman powers?

No you're absolutely right. Like I said I would absolutely love for them to take a Nolanesque approach to WW. The problem would be having WW and Henry Cavill's Supes together would I feel take away from MOS. Cause Snyder is essentially establishing the world as 'our world'. And having more than just 1 superpowered being, not to mention suddenly having to buy greek mythology as real, would just lessen Supermans impact.

I guess I really just want Man of Steel to have a self-contained trilogy like The Dark Knight trilogy. Where Superman is the only superhero and exploring what that means. And not be lessened by being filled with all of the other DC properties.